Furnace.



C. W. STARKER.

FURNACE.

APPLICATION FILED AUG-3| 19H.

Patented Apr. 1,1919.

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FURNACE. APPLICATION FILED AUG.3.19H.

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FURNACE. APPLICATION FILED AUG.319H.

Patented Apr. 1,1919.

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ATLI'ORNEY ATENT @FFIQE.

CHARLES W. STAEKER, 0F PITTSBURGH, PENNSYLVANIA, ASSIGNOR TO WEST-INGHOUSE ELECTRIC 8; MANUFACTURING COMPANY, A CORPORATION OFPENNSYLVANIA.

FURNACE.

Specification of Letters Patent.

Patented Apr. 1, 1919.

Application filed August 3, 1917. Serial No. 184,250.

To all whom it may concern:

Be it known that I, CHARLES W. STARKER, a citizen of the German Empire,and a resident of Pittsburgh, in the county of Allegheny and State ofPennsylvania, have invented a new and useful Improvement in Furnaces, ofwhich the following is a specification.

My invention relates to furnaces'for heating metal for the purpose ofwelding, brazing or other similar operations, and it has particularrelation to furnaces for welding or brazing together the end rings andconducting bars of the secondary members of induction motors.

One object of my invention is to provide a furnace of theabove-described type in which the burners are so arranged as toconcentrate an intense andevenly distributed heating flame around theportions that are to be brazed or welded and in which the intensity ofthe heating flame may readily be varied.

A further object of my invention is to provide means for controlling theoperation of the furnace whereby only certain portions of the work areheated under certain conditions of operation.

In the accompanying drawings, Figure 1 is a view, partially in sectionand partially in side elevation. of a furnace embodying my invention;Fig. 2 is an enlarged plan view of the burners and the piping of thefurnace shown in Fig. 1; Fig. 3 is a view, corresponding to Fig. 1,showing a modification in the arrangement of the burners, and Fig. 4: isa detail view of a portion of Fig. 1.

Referring to Figs. 1 and 2, the furnace comprises a stand or pedestal 1,upon which is mounted a circular frame 2 that is provided with radialribs 3 for supporting a centrally located bearing 4. A verticallydisposed shaft or mandrel 5 is rotatably mounted in the bearing 4 and isprovided, at its lower end, with a worm wheel 6. A worm 7 engages theworm wheel 6 and is mounted on a shaft 8 that is rotatably mounted inbearing hangers 9 carried by the frame 2. The shaft 8 is provided, atone end. with a driving pulley 10 and an idler pulley 11. A second shaft12 is rotatably mounted below and in parallel relation to, the Shaft 8and is adapted to be driven by a suitable motor (not shown). The shaft12 is provided with a driving pulley 14, the Width of which issubstantially equal to the combined widths of the pulleys 10 and 11. Abelt 15 passes over the pulleys 10 and 14: and is engaged by abelt-shifting mechanism 16 that is mounted on a rod 17.

which is longitudinally movable in a direction parallel to the shaft 8.

The upper end of the mandrel 5 is provided with a turn-table 18 uponwhich is mounted an upwardly projecting stud 19. As best shown in Fig.4:, the stud 19 is provided with a collar 20 and is adapted to fitwithin a central opening that is provided in the core member 21 of adynamo-electric machine, which is supported by the collar 20. The coremember 21 is provided with a plurality of conducting bars 22 that extendbeyond the ends thereof and project within an annular depressed portion23 of a conducting end ring 24:. The above-described parts of adynamo-electric machine are substantially thesame as shown and describedin a copending application of Bernard Elshofl', Serial No. 66.732, filedDecember 14, 1915, and assigned to the Westinghouse Electric &Manufacturing Company.

A plurality of burners 25 are circumferentlally arranged around the coremember 21 and are respectively mounted upon a supporting ring 26 that iscarried by the frame 2. Each burner 25 comprises a casting 27 that issubstantially segmental in form and is secured to the upper portion ofthe ring 26 by means of a stud 28 and a nut 29 coacting With a slot 30that is provided in the ring 26. A pair of burner members 31, preferablvcomposed of refractory material, such as fire brick, are mounted withinthe cast1ng'27 and are spaced apart to provide a flame opening 32immediately adjacent to the outer periphery of the conducting end ring24. The specific details of the burner 25 form no part of the presentinvention but are fully show anddescribed in a copending patentapplication of 'W. W. Steven; son, Serial No. 189,338. filed Sept. 1,1917, and assigned to the Westinghouse Electric & Manufacturing Company.The burners 25 are so arranged upon the ring 26. as to provide a space33 between adjacent burners through which the conducting bars 22 and theend ring 24' may be observed.

As best shown in Fig. 2, the burners 25 are provided with rearprojections to which are connected feed pipes 36. Each pipe 36 isconnected to a gas pipe 37 that surrounds the furnace, control valves 38being provided in each of the feed pipes 36. The gas pipe 37 isconnected to a suitable source of supply and a hand-operated valve 39 islocated in the pipe 37 at a point intermediate the burner 25 nearest thesource and the next adjacent burner. Each of the supply pipes 36 isconnected to an air pipe 40 at points intermediate the valves 38 and theprojections 35. The pipe 40 is connected to a suitable means forsupplying air under pressure, and a control valve 41 is located in thepipe 40 at a point intermediate the burner nearest the air supply andthe next adjacent burner.

In the modification shown in Figs. 3 and 4, each burner 25 is adjustablymounted upon a standard 42 that comprisesa base 43 and an upwardlyextending rod 44. The rod 44 is provided with clamping members 45' thatembrace pipes 46 and 47 which are connected to the burner 25 and arerespectively adapted to supply air and gas thereto. .The clampingmembers are held together by a bolt'48, A second set of burners 25 arecircumferentially arranged below the end ring 24, each burner 25 beingso mounted upon the pipes 46 and 47 as to deliver its heating flame in asubstantially vertical direction at points adjacent the depressed ortion23 of the ring 24. The air and gas supply-pipes 46 and 47, respectively,are preferably connected as shown in Figs. 1 and 2.

Having described the various parts of my furnace, the operation thereofis as fol lows:

A quantity of fusible conducting material, preferably in the form ofbrass spelter or other alloy having a good electrical conductivity, isplzred in the spaces of the depressed portion 23 that are not occupiedby the bars 22 or around the portions of the end ring adjacent to thebars 22. The turn-table 18, together with the core member 21, is thencaused to be rotated by shifting the belt 15 over the driving pulley 1O.Gas and air are then supplied to all of the burners 25, and, after themixture has been ignited, the intensity of the flames is regulated bythe valves 38. The continued rotation of the core member enables theoperator to observe the condition of the work, and, when all thesp'elter has melted properly, the furnace is shut down and the coremember withdrawn. If, however, any portions of the end ring 24 areheated unequally, orthe spelter does not melt uniformly, the operatorthen closes the valves 39 and 41 to cut off the gas and airsupply fromall but one of the burners 25. The belt 15 is then shifted to the idlerpulley 11, and,v after the turn-table ing zone of the remaining burner25 by turning a hand wheel 49 that is provided on the shaft 8. In thismanner, all of the spelter may be brought to a uniform state withoutoperating the entire furnace and possibly overheating portions of theend rings and bars that are already properly brazed together.

The operation of a furnace provided with burners arranged as shown inFigs. 3 and 4 is substantially the same as described above, with theadditional advantage that the individual burners may be raised orlowered in accordance with the proportions of the core member upon whichit is desired to work. Furthermore, the provision of vertical heat.- ingflames below the end ring is very desirable when it is desired to bracethe secondary members of machines of large ca-' P ity- While I haveshown my invention in several preferred forms, it is not so limited butis susceptible of various other modifications within the scope of theappended claims.

I claim as'my' invention? V 1. The method of operating a welding furnacecomprising a. rotatable work-carrying mandrel and a plurality of burnerssurrounding said mandrel which consists in continuously rotating saidmandrel while supplying a combustible gaseous mixture to all ofsaidburners and then rotating said mandrel in steps while supplying onlya certain number of said burners.

2. The method of operating a welding furnace comprising a rotatablework-carrying mandrel adapted to berotated by a driving motor, aplurality of burners surrounding said mandrel and means for supplying acombustible gaseous mixture to each of said burners independently of theothers, which consists in continuously rotating said mandrel by saiddriving motor while supplying all of said burners and then manuallyrotating said mandrel in steps'while supplying only a certain number ofsaid burners.

3. In a furnace, the combination with a rotatable mandrel, of aplurality of sets of burners surrounding said mandrel and adapted todeliver flames radially inward, and substantially parallel with respectto the longitudinal axis of said mandrel, respectively.

4. In a furnace, the combination with a rotatable mandrel and a worktable carried thereby, of a set ofburners adapted to deliver flames in aradial direction toward said table, and a second set of burners locatedbelow said table and adapted to deliver flames upwardly toward saidtable.

5. In a furnace, the combination with a rotatable mandrel and a worktable carried thereby, of a plurality of circumferentially arrangedburners that are vertically adjustable with respect to said table.

6. In a furnace,'the combination with a rotatable mandrel and a. worktable carried thereby, of a set of circumferentially arranged burnerssurrounding said table and located adjacent thereto, and a second set ofburners circumferentially arranged below said table, both of said setsbeing vertically adjustable with respect to said table.

7. In a furnace, the combination with a rotatable mandrel, of aplurality of independent segmental burners circumferentially arrangedabout the mandrel, means for adjustably and independently supplying afuel mixture to the burners and means operable to simultaneously shut01f fuel to all save one of the burners.

8. In a furnace, the combination with a rotatable work table, of aplurality of burners arranged circumferentially about the table todirect their flames radially toward it, a plurality of burners locatedbelow the table and circumferentially thereof to direct their flamesupwardly toward the periphery of the table and independent means forvertically adjusting all of the several burners.

In testimony whereof, I have hereunto subscribed my name this 17th dayof July CHARLES W. STARKER.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of latenta,

Washington, D. 0.

